Process of making hexanitrodiphenylamin



i snares rs onnie? JOHN IKflBSHALL, F SWRR-THMORE, PENNSYLTTANIA, ASS'IGNOR T0 E. I. DU POHT DE IEEMOUR$ dz COLVIIAEY, OE WILMINGTON, DELAWARE, A CORPORATION OF DELA- WARE.

PROCESS OF Ml-BEING HEXANITRODIPHENYLAMEN.

issuers,

No Drawing.

To all whom it may concern:

ment in Processes of Making Hexanitrodi phenylamin, and do hereby declare that the following is a full clear, and exact description thereof.

My inventlon relates particularly to the production of symmetrical lafifi xt fi -hcxanitrodiphenylamin in an advantageous manner.

Previously symmetrical hexanitrodiphenylamin has been prepared by the nitration of 2.4-dinitrodiphenylamin with nitric acid of approximately 50% strength to forma 2.4.2 At-tetranitrodiphcny]amin, and then by the nitration of the tetranitrod-iphenylamin with nitric acid of 90% strength to form symmetrical hcxanitrodiphenylamin.

It has previously been considered to be impossible to carry out the nitration of dinitrodiphenylamin to form liexauitrodiphenylamin with mixed nitric and sulfuric acids as is shown for instance by the statement to this eii'ect in Ti Jimsprcngstofl'e, byEscales,

187, and also Z. Gas Scheiss and Spreng. (1913) p. 205, and the above described wasteful method by using nitric acid without sulfuric acid has therefore been found to be necessary in the production of this compound. Furthermore, owing to the strength of the nitric acid used it was necessary to use a lead lined or enameled vesselto resist the action of the acid. 7

The object of my inrention is to provide a process by means of which mixed nitric and sulfuric acids may be used to produce symmetrical hexanitrodiphenylamin, and with such strengths of acids that ordinary iron vessels may be used instead of lead lined or enameled. vessels.

While myinvention is capable of being carried out in many different ways, for the purpose of illustration I shall describe only one Way of carrying out the same hereinafter.

For example-l prepare 2.4.6.2 AK6 -hexw nitrodiphenylamin in an iron water-jacketed vessel, provided with an agitator by introducing into the same with constant agitation, one part by weight of QA-dinitrodiphenyl- 11min at a temperature of about 70 C., togther with five parts 5 by weight of mixed Specification of Letters Patent.

Patented Jan, 6, 1920.

application f led March 20, 1919. Serial No. 283,843.

acid containing approximately 30% nitric acid, 55% sulfuric acid, and 15% Water. Thereafter the temperature is raised to from 80 to 90 (l, in any suitable manner, and the agitation is continued atthis tempera ture for'npproximately one hour. There upon the mixture is cooled to 30. (3., and the solid 2.42 .4 tetranitrodiphenylamin is separated from the spent acid by filtration. The material thus obtained, in an acid condition, is added at 70 0., to five parts by weight of mixed acids containing 20% nitric acid, 75% to 80% sulfuric acid and 5% 'to 0% water in the vessel previously re ferred to. The mixture is then raised to 80 to 90 0., and kept at this temperature for from one to two hours. Thereafter the solid 2A62 4 .6 hcxanitrodiphenylamin is separated from the spent acid by filtration,

is drowned in water, and washed with hot water until freed from acid. Afterward it is centrifuged from the wash water and dried.

While I have described my invention above in detail, I wish it to be understood that many changes may be made therein without departing from the spirit of the same.

1. The process which comprises treating 2.i-dinitrodiphenylamin at an elevated temperature with mixed nitric and sulfuric acids until a substantial proportion of said dinitrodiphenylamin has been converted into 2.4.2 ?-tetranitrodiphenylamin.

2. The process which comprises treating 2. i-dinitrodiphenylamin with mixed nitric and sulfi'iric acids under conditions so regulated as to form 2.4.2 A 'tetranitrodiphenylamin, and then, further nitrating the resulting tetranitrodiphenylamin with mixed nitric and sulfuric acids.

3. The process which comprises nitrating 2Jl-dinitrodiphenylanlin with mixed nitric and sulfuric acids under conditions so regudiphenylamin which comprises treating said dinitrodiphenylamin with mixed nitric and sulfuric acids, the strength of the acids used"- being such that they do not attack iron.

5. The process whlch comprises treating perature-With mixed nitric and sulfuric acids under conditions so regulated as to form tetranitrodiphenylamin, the strength of the acids used being such that they d0 not attack 11'01'1.

6.v The process which comprises treating 2.4-dinitrodiphenylamin with mixed nitric and sulfuricacids under conditions soregulated as to form 2.4.2 Ac -tetranitrodiphenylamin, and then further nitrating the re sulting tetranitrodiphenylamin with mixed nitric and sulfuric acids, the strength of the acids used being such that they. do not attack iron.

7. The process which comprises treating 2.4-dinitrodiphenylamin with mixed nitric and sulfuric acids under conditions so regulatedas to form 2A2 .4 -tetranitrodipheny1- amin, and then further nitrating the tetranitrodiphenylamin at an elevated tempera ture with mixed nitric and sulfuric acids to form 2.4.6.2 .4 .6 -hexanitrodiphenylamin,

the strength of the acids used being such that r they do not attack iron.

18'. The process which comprises nitrating 2.4-dinitrodiphenylamin with mixed nitric and sulfuric acids under conditions so regulated as to form 2.42 .?-tetranitrodiphenylamin, and then further nitrating the tetranitrodiphenylaminwith mixed nitric and sulfuric acids, the mixed acids containing in the first nitration 30% nitricacid and in the second nitration 20% nitric acid. 7

9. The process which comprises treating 2.4-dinitrodiphenylamin with mixed nitric and sulfuric acids under conditlons so regulated as to form 2A2 .4 -tetranitrodiphenylk amin, and then nitratin the tetranitrodiphenylamin at an elevated temperature with, 40

mixed nitric and sulfuric acids to form 2.46.2 .49.6 hexanitrodiphe'nylamin, the mixed acids containing in the first nitra tion 30% nitric acid and in thesecond nitration 20% nitric acid.

10. The process which comprises treating dinitrodiphenylamin with mixed nitric and sulfuric acids, the treatment being carried out at from 80 to 90 C.

11. The process which comprises treating 2.4-dinitrodiphenylamin with mixed nitric In testimony' that I claim the foregoing I have hereunto set my hand.

JOHN MARSHALL. Witnesses LYMAN L. TrrUs, GEO. H. GREGG. 

